The present invention relates generally to electrical connectors of reduced size, and more particularly to surface mount miniature connector assemblies with improved means for holding the components of the connector assembly together.
The trend of the electronics industry is to constantly reduce the size of electronic devices. Many electronic devices rely upon circuitry formed upon various printed circuit boards. These printed circuit boards must be joined together with connectors in a manner to effectively and reliably interconnect the circuits on one circuit board to the circuits on another circuit board.
In order to permit the connection of two circuit boards in parallel planes and to reduce the size of electronic devices, the connector industry developed the surface mount connector. A typical surface mount connector utilizes a plug-type male connector component that unites with an opposing receptacle-type, or female connector component. Both connector components are of low profile, allowing the circuit boards to be closely spaced to each other. When the connector components are engaged together, the mating terminals of the connector components form an electrical connection between the circuits of the two circuit boards.
It is desirable to retain the connector components in engagement with each other and to fulfill their need, locking mechanisms have been developed for such connectors. The use of locking mechanisms that are separate from the connector components may lead to more complex structure and larger sizes of connectors. When the locking mechanisms are formed as part of the connector component housings, they waste space that could be used on the connector and because the mechanisms are made entirely from plastic, such as that described in U.S. Pat. No. 5,199,884, issued Apr. 6, 1993, the locking mechanism will not be that strong.
In some connection applications the size of the connector portions themselves are extremely small, in what is known as the "micro-miniature" range where the connectors may have length and width dimensions as small as approximately 5 mm by 2 mm and height dimensions as small as approximately 2 mm. The approach in the industry with small size connectors is to utilize frictional force to hold the connectors together. However, such frictional forces will not always reliably resist accidental unmating. Additionally, insertion forces cannot be so excessive as to cause difficultly in mating such connectors. Accordingly, the need exists for a surface mount board to board connector that has a high degree of mechanical integrity and a sufficiently strong withdrawal force and a sufficiently light insertion force.
The present invention is therefore directed to an electric connector assembly which overcomes the aforementioned disadvantages and assures a stable holding force to hold the associated connector components together no matter how small the connector size.